The best strategy, actually a win-win over the long haul, is to JUST buy Bitcoin for the amount you can afford once a week / month.
You do not need to try to make money ON Bitcoin, you just need to try to buy it in addition to your financial capabilities, but at the same time so that your life does not suffer and does not depend on these costs.
In 10 years, you will say thank you to yourself for simply methodically and regularly buying and accumulating Bitcoin. Of course, it is better to try to do this on strong drawdowns or a falling market. But you don't have to bother and take at any price - over a long distance from 10 years, you will be in the black in any case and will not lose anything, but only gain what others will only dream of all their lives.
Bitcoin is a means of accumulation and storage, your personal savings that will not be lost, no one will take them away (if stored correctly) and will give you good capital in the future. Where is it better to buy, where to store and what coins to pay attention to, you can ask by writing in private messages.